Cossor themselves seem to be very poor at
documenting early sets some of which don't appear even in their own
documentation. None of these sets have been restored by me so they
are all pretty much as I got them. As far as I know all of these
kit sets are represented here.

1927 Melody
Maker

BK229

1929 Melody
Maker

BK4

1930 Melody
Maker

In 1927 Cossor keen to promote the use of their valves created a
pamphlet for a 3 valve battery radio with a list of parts that
would be stocked by most Radio suppliers the pamphletcost 6d. It included the instructions to wind your own
coil. This set has no Cossor model number.

The set is 3 triodes (missing on this one until I restore it.
They would have originally been Cossor Stentor valves

These early sets are relatively common and obviously so
successful Cossor went on to put a kit of parts together and offer
the complete kit. The Cossor Valve Manual 1937-8 refers to this set
as the 1927 Melody Maker. They are easily spotted by the large
horizontal coil (6” by 3”) between the two tuning
capacitors on the front panel.

These early sets were obviously very popular so in 1928 Cossor
produced a fully knock down kit with a purpose designed metal
cabinet BK229 Taking a guess at the model numbers meaning
Battery Kit Version
2model year1929model years are always are
always the following year, everyone want to buy next years model
its just a marketing ploy.

These 1928 Melody makers are often found in poor condition and
with one set of coils missing since you need to plug in a set of
coils to match the waveband you wish to cover Long Wave or Short
Wave (now referred to as Medium Wave).

The next set in the series is the series and its 2 sister
sets are not very common in fact they seem to have been something
of a marketing disaster probably because as a kit set they were
very expensive. Cossor Model Number BK4 (there does not seem to be
reference to a BK3)

The set has a very large steel cabinet with a
striking Escutcheon with only a single tuning control. This was
achieved by using a factory assembledTuning
assemblyReferred to as a “Synchronised Control Unit”
This contains all the coils and capacitors as well as band
switching and is factory aligned.Unlike the other
sets the 3 sets using this cabinet could not “flat
pack”

MK530

All Electric Melody
Maker

The second in this series of sets Cossor Model
number MK530 MK standing forMainsKit.

Shown here without its case.

This set was also marketed 1929 to 1930 and uses the same
pre aligned tuning unit as the BK4 but in addition has a factory
assembled mains power supply module. Cossor obviously didn't want
to kill off the few customers they still had. From the outside it
looked just the same as the BK4 above.

BK531

Empire Melody
Maker

The next set seems to be out of sequence but by
model number it is next BK531 the “Empire” Melody Maker, Not to be
confused with the similar looking 234. This set adopted the classic
two wooden end cheeks wood lift up lid metal panels front and rear
that most associate with the early Cossor Melody Maker Kits, Its
back to two knob tuning and waveband switching is by switches on
the top of the coils. This set seems to have recaptured Cossors
lost market since there are still quite a few of these
around.

BK631

4 Valve Screen Grid Melody
Maker

Next is a very rare set the BK631 Marketed as the 4 Valve
Screen Grid Melody Maker. This is basically a BK4 with an
additional valve added. I suspect this was a way to clear the
shelves of the parts left unsold from the BK4 and MK530 and was on
sale at the same time as the Empire Melody maker. It has the
addition of a gain control (filament control on the SG valve)
otherwise externally it looks just like a BK4. In the instruction
sheet for the BK631 it boasts that more than 250,000 Melody Makers
are in daily use. I don't currently have one of these in my
collection.

Empire Melody Maker Model
234

Empire Melody Maker
Model 235

Now we come to the last of the series when more
conventional Cossor numbering system is adopted, more on Cossor
numbering conventions later. The 234 is the most common of these
sets still found today.

These two sets both originally for sale in 1931 The 234 is
a battery set Battery the 235 is mains.

They would have considered as 1932 model year. The 234 and
the 235. The battery model 234 is probably the most common of all
of the lift up lid style Melody Makers. This set uses a steel base
board for the first time and a push pull waveband selection that
was to be used on many other sets over the next couple of years.
Considering the lift up lid the mains power supply on the 235 all
looks a bit lethal. There are holes in the lid to screw it down
since no access inside the cabinet is needed for normal operation,
however I don't expect many were ever screwed
down.

Circuit for
BK229

Cossor drawing of the Synchronised Control
unit.

These were used in the BK4, BK530 and the BK631 Kit
sets.

These were supplied as a factory assembled unit making
the kit much simpler to assemble. The factory pre alignment means
that there is sufficiently good tracking to remove the need for two
tuning knobs as with the other sets both before and after this
series.

The aluminium screening can is also used as the common
connections for the HT and LT.

Not shown on this drawing are the connections of which
there are 4 underneath (just discernable toward the bottom left of
the unit) 3 more at the rear in a strip, a dedicated connection
(pre-made) to connect to the anode cap of the SG valve and finally
a knurled terminal which is the common connection to the
case.

Despite the similar Escutcheon this unit is not used in the
regional receivers.